Hi guysI just talked to Don a few weeks back. His audio company is gone :(He is actually in the hospital (might be out now) he had some cancer removed and has had a rough time so I wouldn't be looking for too much response from him yet.Don ported the WO by cutting a slot into the opening of the horn. It was pretty loud, but it was very much so a one note wonder.We played around with moving the speaker baffle to try and get more SPL too. Angling the baffle is definitely not the way to go for SPL.Other than that, the enclosure doesn't do too much as far as tuning goes. The bigger the back chamber the lower the tuning. The box has a pretty good in car boost around 40hz which makes it sort of generic as most cars cabin gain is near that freq. I wouldn't want to try and tune it as is to a more specific freq. I do have a design that we never built though that you might be interested in. The rear chamber is bigger and the chamber is ported to provide more gain at the tuning freq of the port. I will post that pic as soon as I can find my design notes. I would love to see somebody take that on.To give you some ideas, I ran a WO 8" in a 240sx and was getting 150-151 db out of itWe also ran a 10" WO in a 4 door blazer and got similar #s with that. We tried to go up to a 12" version and got to the mid 150s with it, but never really pushed hard to see what the design was capable of. I actually got off track at that point and started competing with the slot vented enclosures and straight rear loaded horns. They got big and ugly too lol.What kind of car, woofers, amp, etc are you looking at putting together? I am sure I can offer some ideas on this one.

[quote author=musgofasa link=1157009897/0#5 date=1157484255]Hi guysI just talked to Don a few weeks back. His audio company is gone :(He is actually in the hospital (might be out now) he had some cancer removed and has had a rough time so I wouldn't be looking for too much response from him yet.Don ported the WO by cutting a slot into the opening of the horn. It was pretty loud, but it was very much so a one note wonder.We played around with moving the speaker baffle to try and get more SPL too. Angling the baffle is definitely not the way to go for SPL.Other than that, the enclosure doesn't do too much as far as tuning goes. The bigger the back chamber the lower the tuning. The box has a pretty good in car boost around 40hz which makes it sort of generic as most cars cabin gain is near that freq. I wouldn't want to try and tune it as is to a more specific freq. I do have a design that we never built though that you might be interested in. The rear chamber is bigger and the chamber is ported to provide more gain at the tuning freq of the port. I will post that pic as soon as I can find my design notes. I would love to see somebody take that on.To give you some ideas, I ran a WO 8" in a 240sx and was getting 150-151 db out of itWe also ran a 10" WO in a 4 door blazer and got similar #s with that. We tried to go up to a 12" version and got to the mid 150s with it, but never really pushed hard to see what the design was capable of. I actually got off track at that point and started competing with the slot vented enclosures and straight rear loaded horns. They got big and ugly too lol.What kind of car, woofers, amp, etc are you looking at putting together? I am sure I can offer some ideas on this one.

Robert [/quote]

Hi RObert ! ty for answer ! I didnt know that about Don i hope that everything is OK with him now ??

He told me that his suppliers were wanting him to buy more stuff than he could handle so it just got to be too much and he stopped building the inhumans. He did have someone move the forum though to www.teamspl.it

There are a lot of SPL guys on both of those forums that have some good game now. The WO certainly isn't used enough to get many answers from those guys (More xp with it right here) but if SPL is what you are after, those are some good places to start. There are a lot of guys on there I used to compete with.

Has anyone thought of just building a second lid onto a stock WO, built up about 2 inches higher, then porting the rear chambers into the space between the first and second lids? With only one side open this would make for a very large, low tuned slot port. It certainly wouldn't be as loud as the exponential port below it, however, it would have a very low tuning and may improve the overall sound of the enclosure...

I like this ideaI think you could even open the back side of the port with a small sized vent into the cavity and adjust the size of it to change the tuning?This might be more creative than even I want to get started on lol, but it would be interesting to say the least.The WO as is seems to have a pretty good boost around 45 hz (maybe a little lower?) which would indicate that the horn is unloading prematurely and acting closer to a standard 4th order so by porting the rear side of the driver with a tuned port, I would assume you would gain efficiency like a 6th order does, which means louder and more tuneable.So if we make the bottom side a very long port, I wonder if it would smooth out the overall response? Might make it sound better in a HT situation?Of course for str8 SPL I think that we would want the enclosure to be more efficient and house a higher power driver. The only problem I have run into with this is that the WO is fairly flimsy in regards to SPL because of the removable lid. It holds well, but it is a different type of constraint than the conventional vented chambers most guys are using. This is the reason we went to a bigger "ported" chamber and started making the ports expand like a horn mouth. This took away the necessity to tune the port as it unloaded at the resonant frequency on it's own. Of course we are talking about a wall and big subs in a small car lol.I am still interested to see if the WO can be made to do more, although Don and I had this conversation for months, neither of us ever built more of them. I think it just wasn't financially viable when we were using the bigger stuff to compete. Anyone feel like some sawdust? Have saw will travel! Heck at this point, I will come to someone's house and build it for them if they have the tools! (Oh and the materials would help lol)Personally, I like throwing the ideas around as much as building, but it just isn't as satisfying as powering it up and listening.

This would be testing my knowledge of horns methinks :-* Just to oversimplify things let me ask a question.Doesn't the expansion of a horn basically release the sound wave into open air at a point where the frequency's size is equal to the mouth area? Or at least in this instance 1/4 wavelength of the frequency?If this is the case, then the longer the horn gets, the more control over the wavefront it would have therefore providing the speaker with a cushion to load against and reinforce the wave. At least that is how I see the expansion helping to make the horn more efficient than a typical box.If anyone has a simpler explanation, that is what I want. i have read a bunch of books on the subject and had several conversations with Mr. Bruce Edgar about it, but the complications are all mathematics and little theory really.That being said, I believe that the effect of a longer horn is a more level and smoother sounding response, but the only output gain being from the improved power handling and limited excursion created by the pressure back against the woofer at a given frequency.Now I am getting too technical to be practical though. Any thoughts? To get more SPL basically you have to increase the power, increase the cone area, increase the excursion, or increase the efficiency of the entire system (of course any combination of the above multiplies). So, in theory this means that the most SPL producing set up would be a chamber that has an open horn on either side of the driver, but there is no way to model it that I know of. Could one say that a horn on both sides would double the output? Of course wouldn't the 2 horns be 180 degrees out of phase unless they were different lengths with different expansion ratios.I had this conversation with Mr. Edgar and he laughed at the complexity of it at the time saying it was more trouble to do on paper than in practice and I should build it and let him know how it turned out lol.Ahh to have my shop back. On the good side, my best friend has a saw and a shop and I have some other tools. I just need a brad nailer and a good compressor and I am on my way again. The WO is a bass enclosure so working with more horns and more size is probably not going to affect it as much as changing the chamber size, power handling, and excursion of the drivers. Who wants to be the first to build one of these monsters we have described? Personally I am up for the port out the bottom idea with the opening on the same side as the mouth. I might build that with a really, really low tuning frq just to see if it sounds good for a TV stand in my HT. Anybody know of a 10" with a really low Fs? (Like below 20hz)Ok enough books for today. I am getting carried away lol.

A good 10" with an Fs below 20hz can be found at the peerless section of parts express, its some pricey though...

The WO isnt really a horn, more like either a resonator or exponential port, so modeling it as a horn is optimistic at best, ridiculous is more likely. I am NOT saying this is not a good enclosure, but it is very difficult to model something like this.

build another WO, match holes in the bottom of it to holes in the top of existing WO and have the drivers mounted there with the mouths opening opposite one another. Put this in the middle of a shorter wall with the openings faced into opposing corners and you start to get close to a horn response.